And many of them wind up broke because they are high income earners but turning high income into large wealth isn't easy when your income earning days are limited by age.
Meanwhile these leagues operate monopolies and a bunch of billionaires set salary caps because they just can't possibly pay more than some made up number.
At least MLB and the competitive landscape of international soccer(football) get players paid something close to their actual value.
But the NBA/NFL is a god damned joke of inequity but heaven help the players association if they go on strike.
MLB they don't make anywhere near their actual value, guys are held down arbitrarily in their earning power for years to the point where players who peak early end up screwed out of tens if not hundreds of millions of dollar in net value add that they don't get because oops, didn't hit free agency early enough. Matt Harvey probably missed out on $40-50M because his arm gave out early after several years of dominance for instance. NFL and NBA labor stoppages end up shunted onto the players and owners do everything they can to increase financial burden on players to disincentivize that (ever wonder why instead of punishments being suspensions blanket cause, they're almost always money first unless it's an egregious act? That's why).
None of the leagues pay commensurate to value, and that's not even covering the piss poor pension plans, the abandonment of players from more than 20 years ago, the complete lack of a comprehensive lifetime health plan, any sort of legitimate financial guidance and the monopoly they have on keeping these players young, stupid, and unaware by forbidding them access or even to have a conversation with a financial adviser beyond "approved" ones by the league which means "they paid the right bribes and signed the right papers" and isn't a signal of any sort of real legitimacy. Evidenced by the overwhelming number of them that end up sued for theft of wages.
It's a microcosm of how labor is treated in the west. Even those with ostensible power and wealth behind them are ultimately nothing to the great meat grinder of unlimited capital poised against them. You can be the richest worker in the world, but you're still just a worker.
It's gross, guys end up crippled for life and can't even get a measly pension.